All air handlers, manufactured for both residential and commercial use, have the same distinct components: a fan or blower to move the air, a heat-exchanging coil to cool the air, and an outer casing to enclose the blower and the heat-exchanging coil. Most modern air handlers also include some kind of electronic control unit. In addition, there is typically a shelf or cross-member in the outer casing provided to support each of these main components.
The heat-exchanging coil is placed at a first end of the air handler, with the blower next to it. In operation, the blower pulls air from an inlet at one end of the air handler, and through the heat-exchanging coil, which cools or warms the air. Then the blower blows the cool or warm air out through an outlet on the other end of the air handler. As a result, the entire inside of the housing is cool or warm, and needs to be insulated.
The shelves that support the blower and the heat-exchanging coil are typically attached to the outer casing with fasteners, such as screws or bolts, which pass through the wall of the outer casing as well as any insulation between the components and the area outside the outer casing. In fastening the shelves to the outer casing by the fasteners, the insulation gotten stuck between the shelves and the outer casing will be compacted in the vicinity of the fastener. This reduces the effectiveness of the insulation, causing local temperature differentials. It is inefficient. In addition, it can provide locations for the formation of condensate if the air is cooled. In particular, condensate can form on the fasteners, especially if the units are installed in high-humidity and high-temperature areas.
It would therefore be desirable to provide a way of securing a blower and a heat-exchanging coil to an outer casing without providing areas of temperature differential, or locations where condensate can easily form.